1. Field of the Invention
The present invention relates to a dereverberation system and a dereverberation method.
2. Description of the Related Art
There has been proposed a semi-blind MINT method extended blindly from a MINT method fulfilling a rigorous inverse filter (refer to: K. Furuya and A. Kataoka, “Robust speech dereverberation using multichannel blind deconvolution with spectral subtraction”, IEEE Trans. on Speech and Audio Processing, vol. 15, no. 5, pp. 1579-1591, 2007). The validity thereof has been reported as an application in dereverberation for a remote meeting system.
However, the semi-blind MINT method is configured to design the inverse filter after information of a transfer system has been estimated blindly in 2 steps. Accordingly, it is needed to update the information of the transfer system and the inverse filter in a defined constant time frame in order to perform the processing adaptively. Thereby, it is difficult for the semi-blind MINT method to perform the processing adaptively in a high speed. Moreover, since the semi-blind MINT method is principally an extension of the MINT method, it will be restrained from being used in such a condition as, for example, one channel or the like, where the rigorous inverse filter cannot be deduced.